JS Minifier - Compress JavaScript Files for Faster Page Loads

JavaScript minification is essential for production websites. It removes unnecessary characters and shortens identifiers to reduce file size, making pages load and execute faster. Terser, UglifyJS, and SWC are popular minifiers in the JS ecosystem.

What JS Minification Does

• Remove all comments (single-line and multi-line)
• Remove whitespace, line breaks, and indentation
• Shorten local variable and function names (myVeryLongVariableName becomes a)
• Remove dead code (unused functions/variables with tree-shaking)
• Simplify expressions (true becomes !0, false becomes !1)

Minification vs Obfuscation

Minification makes code smaller but still readable. Obfuscation makes code intentionally hard to understand (string encryption, control flow flattening). Use obfuscation only when you need to protect intellectual property.

How Much Can You Save?

Typical savings: 30-50% from whitespace/comment removal, up to 70% with variable name shortening. React's production build minifies and tree-shakes, often reducing a 1 MB bundle to 200-300 KB.

Free JS Minifier

Use SnapSum JS Minifier - paste your JavaScript, get minified code instantly. Option to preserve function names for debugging. 100% browser-based, no upload.